非均匀地震作用下隧道位移反应分析

根据多点地震动合成方法,考虑地震波的随机性和行波效应,生成非均匀多点地震动加速度时程曲线,在此基础上,运用FLAC3D分析隧道在非均匀性地震荷载作用下的响应特征及其影响因素。引入非均匀影响系数η和最大最小位移比Φ描述地震作用下隧道位移反应规律。分析结果表明,隧道的位移反应和地震的空间非均匀性对隧道位移的影响随埋深、侧压系数增加而减小;随地震动振幅的增加而增加;随地震动卓越频率的增加而减小;随地震动持时的增加而增加。非均匀影响系数η和最大最小位移比Φ表现出和位移相同的变化趋势。

Seismic Response Analysis of Tunnel Under Non-uniform Seismic Loading

According to the synthesis of multi-point ground motion method, the non-uniform seismic acceleration-history, which is created on the basis of the combination method, has been input into FLACaD software. The non-uniform influence coefficient η and the ratio of maximum displacement and minimum displacement Ф have been introduced to describe the regularity of displacement under the seismic loading. It is reported that the displacement response of tunnel decrease with the increasing of the buried depth, the lateral pressure coefficient, and the frequency of seismic waves. However, the displacement response of tunnel increase with the amplitude and the duration of seismic waves. The effects of the displacement response by the non-uniform characteristics of seismic loading, the coefficient η and Ф have the same changing trends.